The present invention relates to a web splicing apparatus and method for forming a splice between the trailing end of an advancing web of paper or other material and the leading end of a new web of material.
In the production of spirally wound composite containers and other similar products, a relatively narrow web of paper is fed at high speed from a supply roll to a tube winding machine. To permit the continuous operation of the tube winding machine upon the supply roll being emptied, the leading end of a web from a new supply roll must be secured to the trailing end of the expiring web. To facilitate this operation, a splicing machine has been previously proposed wherein the web advances through the splicing machine, and then through a festoon type accumulator, before proceeding to the tube winding machine. The leading end of the new web is fed into the machine by hand, and held in a ready position by a vacuum system, and as the supply roll is emptied, the trailing end of the expiring web is gripped and held stationary by the splicing machine. Then the leading end of a new web is moved into alignment with the trailing end of the expiring web and joined thereto by a piece of adhesive tape to form a butt splice. The advance of the joined web is then restarted, so that the new web is advanced through the festoon type accumulator and to the tube winding machine. The festoon type accumulator permits the web to be continuously supplied to the tube winding machine during the splicing operation, so that the tube winding operation can proceed without interruption.
The above described splicing machine is not completely satisfactory however, since the manual placement of the leading end of the new web in the machine presents a safety hazard, and since an accurate alignment of the leading end with the trailing end is not assured.
Several other types of butt splicing machines have been proposed for use in association with tube winding machines of the type as described above. The butt splicer disclosed in U.S. Pat. No. 4,769,098 is representative of these prior splicers, and it comprises a new web preparation assembly which is used to prepare the leading edge of a new web, a new web and tape holding assembly used to hold a portion of the new web and a strip of adhesive tape in preparation for splicing, a nip assembly used to clamp the expiring web, and a cutting and adhering assembly that simultaneously cuts the expiring web and causes the trailing end of the expiring web to be adhered to the leading edge of the new web.
While the apparatus described in the referenced patent is no doubt satisfactory for many production processes, it is believed that the apparatus would not be able to reliably cut and splice a damaged, wrinkled, or creased paper web.
It is accordingly an object of the present invention to provide an improved splicing apparatus which is able to reliably cut and splice webs of paper as they are sequentially fed to a tube winding machine or the like, and which may be safely operated.
It is also an object of the present invention to provide an improved butt splicing apparatus and method which results in the formation of a splice having adequate strength to pass through the remainder of the manufacturing process and to maintain its integrity in the final product.
It is a further object of the present invention to provide a butt splicing apparatus and method which maintains precise lateral alignment of the web segments to allow their passage through the remainder of the manufacturing process without degradation.
It is another object of the present invention to provide a butt splicing apparatus and method which is able to achieve a minimal spacing between the trailing end of the expiring web and the leading end of the new web to allow it to pass through the remainder of the manufacturing process without degradation and to maintain the integrity of the final product.
It is a more particular object of the present invention to provide a butt splicing apparatus and method which provides a clean cut and square edge for both the trailing end of the expiring web and the leading end of the new web and which invariably places the two ends at a consistent reference location on the splicer so that they may be pre-aligned and precisely joined.